count had a value of four (two in each direction) and this was simply conflated over, it would give both NCTCOG segments a value of four, when in reality they should both have a value of two. For any segments that were assigned a value from the TxDOT Roadway Inventory, OpenStreetMap (OSM) data was used. This was done in the same manner as with the TxDOT data, i.e., spatial conflation with adjustments to account for differences in data representation. Finally, for any segments that were still unknown, they had their values filled based on the most commonly occurring values for the same functional classification and road name, except for residential roads. This is because local roads tend to not have values, and where they do have known values, there’s a higher chance of that location being enough of an outlier to warrant collecting data. Any residential roads without a known value from one of the above sources was assigned a lane count of two. Annual Average Daily Traffic (AADT) AADT was not present in the NCTOG data. AADT was available in the TxDOT roadway inventory and was conflated onto the network. Like lane count, the TxDOT AADT data was fully populated within itself, but not did cover all roadway segments. Adjustments were made to ensure the final AADT values assigned correctly accounted for differences in data representation. For segments without AADT, estimated AADT from Replica were used. Since these are modeled volumes, they were fully populated and able to fill in most of the remaining data gaps. The only gaps remaining were instances in which minor differences in segment geometry prevented a spatial match. For these, values were estimated based on the most common occurring values for segments of the same name and functional classification. Unlike lanes, residential streets were included in this stage, as most local roads had values from TxDOT or Replica, which reduced the impact of outlier observations. Speed Limit Speed limits came from several sources. For segments within the City of Fort Worth, data was available from the City of Fort Worth. Outside the city, speed limit coverage varied within the NCTOG data, although any known values that were present were incorporated into the network. TxDOT data contained speed limit data, although it only had coverage for on-system roadways. This data was conflated onto the network to fill gaps. After this, OSM speed limit data was
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